Along with the recent development in the information communications technology, roles of server systems used for the Internet connections or storage are gradually becoming larger.
A server system has a power supply unit and a blade server mounted in one rack. Among them, the power supply unit is supplied with power from wirings in a premise of a data center and is used for supplying this power to the blade server. However, when a blackout occurs in the data center, the power is not supplied to the blade server.
For this reason, an uninterruptible power-supply apparatus such as a UPS (uninterruptible power supply) is sometimes provided in the rack of the server system in addition to the above-described power supply unit.
The uninterruptible power-supply apparatus includes a storage battery for backup. Thus, even though the blackout occurs in the data center as described above, the power generated from the storage battery is supplied to the blade server to prevent the operation of the blade server from being stopped due to the blackout.
As described above, the uninterruptible power-supply apparatus functions to back up the power of the server system and it is thus preferable to improve its performances.
PATENT DOCUMENT 1: Japanese Laid-open Patent Publication No. 08-20554
PATENT DOCUMENT 2: Japanese Laid-open Patent Publication No. 2007-202241